Washing system of machine tool

ABSTRACT

A washing system that can reliably remove chips attached to the surface of a jig on which a workpiece is placed. The washing system includes a nozzle, a manipulator for moving the nozzle, an imaging part for capturing an image of a region on which a workpiece is placed, a chip detecting part for detecting a chip in the region based on the image captured by the imaging part, a arrangement determining part for determining a position and posture of the nozzle when the fluid is sprayed to the chip, a manipulator controlling part for controlling the manipulator so that the nozzle is located at the determined position and posture, and a fluid supplying part for injecting, through the nozzle, the fluid that has been supplied to the nozzle.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a U.S. Continuation Application of U.S. patentapplication Ser. No. 15/228,435, filed Aug. 4, 2016, which claimspriority to Japanese Patent Application No. 2015-159198, filed Aug. 11,2015, the contents of such applications being incorporated by referenceherein.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The invention relates to a washing system for a machine tool.

2. Description of the Related Art

A system for removing chips generated during working of a machine toolby injecting fluid to the chips has been known (for example, JapaneseUnexamined Patent Publication (Kokai) No. 10-118884).

In this technical field, technologies for reliably removing chipsattached to the surface of a jig for disposing a workpiece have beenrequired.

SUMMARY OF THE INVENTION

In an aspect of the invention, a washing system of a machine toolincludes a nozzle capable of injecting fluid, a manipulator which movesthe nozzle, an imaging part which images a region on which a workpieceto be processed is placed, a chip detecting part which detects a chippresent in the region based on an image imaged by the imaging part, andan arrangement determining part which determines a position and postureof the nozzle when the fluid is injected to the chip detected by thechip detecting part.

Further, the washing system includes a manipulator controller whichcontrols the manipulator so as to arrange the nozzle at the position andposture determined by the arrangement determining part, and a fluidsupplying part which supplies the fluid to the nozzle so as to injectthe fluid through the nozzle when the nozzle is arranged at the positionand posture.

The arrangement determining part may determine the position and postureso that the fluid injected from the nozzle can blow away the chip in apredetermined direction. The imaging part may image the region beforethe workpiece is placed on the region, and image the region after theworkpiece is machined by the machine tool and removed from the region.

The chip detecting part may detect the chip present in the region bycomparing the image imaged before the workpiece is placed on the regionwith the image imaged after the workpiece is removed from the region.

A priority zone may be predetermined within the region. The chipdetecting part may detect the chip present in the priority zone based onthe image. The arrangement determining part may determine the positionand posture when the fluid is injected to the chip present in thepriority zone.

The imaging part may be moved by the manipulator. The manipulatorcontroller may operate the manipulator so as to arrange the imaging partat a plurality of positions at which the imaging part can image theregion. The imaging part may image the region at each of the pluralityof positions.

The imaging part may image the region again after the fluid is injected.The chip detecting part may detect the chip remaining in the regionafter the fluid is injected, based on the image imaged by the imagingpart after the fluid is injected.

The manipulator controller may operate the manipulator so as to arrangethe nozzle at the position and posture again when the chip detectingpart detects the remaining chip. The fluid supplying part may supply thefluid to the nozzle so as to inject the fluid through the nozzle again.

The washing system may further include a warning generating part whichgenerates a warning when the number of injections of fluid from thenozzle exceeds a predetermined number.

BRIEF DESCRIPTION OF THE DRAWINGS

The above or other objects, features and advantages of the inventionwill be clarified by the detailed description of exemplary embodimentswith reference to the accompanying drawings, in which:

FIG. 1 is schematic view of a washing system according to an embodimentof the invention;

FIG. 2 is a block diagram of the washing system shown in FIG. 1;

FIG. 3 is an enlarged view of the nozzle shown in FIG. 1;

FIG. 4 is a top view of the jig shown in FIG. 1 as seen from the upwardin FIG. 1;

FIG. 5 is a flowchart of an example of an operation flow of the washingsystem shown in FIG. 1;

FIG. 6 is a flowchart of an example of a flow of step S4 in FIG. 5;

FIG. 7 is a flowchart of an example of a flow of step S6 in FIG. 5;

FIG. 8 shows an example of an image imaged at step S3 in FIG. 5;

FIG. 9 is a view for explaining step S12, in which an example of theposition and posture of the nozzle when injecting the fluid to a chippresent in a first zone is illustrated;

FIG. 10 is a view for explaining step S12, in which an example of theposition and posture of the nozzle when injecting the fluid to a chip ina third zone is illustrated;

FIG. 11 is a view for explaining step S12, in which an example of theposition and posture of the nozzle when injecting the fluid to a chip ina fourth zone is illustrated;

FIG. 12 is a block diagram of a washing system according to anotherembodiment of the invention; and

FIG. 13 shows an example of the position and posture of the nozzle wheninjecting fluid to a chip in the washing system shown in FIG. 12.

DETAILED DESCRIPTION

Embodiments of the invention will be described below in detail based onthe drawings. First, a washing system 10 according to an embodiment ofthe invention will be described with reference to FIGS. 1 to 3. Thewashing system 10 is for washing the inside of a machine tool 100.

The machine tool 100 includes a processing machine 102, a jig 104, and amachine tool controller 106. The processing machine 102 processes aworkpiece (not shown) to be processed, which is placed on the jig 104,in accordance with a command from the machine tool controller 106.

The jig 104 is detachably mounted inside of the machine tool 100.Various kinds of jigs other than the jig 104 shown in FIG. 1 may beprovided depending on the kind of a workpiece to be processed. The jig104 is mounted inside of the machine tool 100 before processing on theworkpiece, and the workpiece is placed on the jig 104.

Processing the workpiece generates chips. As the machine tool 100operates, such chips may attach on the surface of the jig 104. Thewashing system 10 according to this embodiment removes the chipsattaching on the jig 104.

The washing system 10 includes a controller 12, a robot 14, an imagingpart 16, a nozzle 18, and a fluid supplying part 20. The controller 12directly or indirectly controls each component of the washing system 10.The controller 12 is connected to the machine tool controller 106 so asto be able to communicate with the machine tool controller 106. Thecontroller 12 carries out a washing operation for the machine tool 100while communicating with the machine tool controller 106.

The robot 14 is e.g. a vertical articulated robot, and includes a robotbase 22, a revolving drum 24, and a robot arm 26. The robot base 22 isfixed on a floor of a work cell. The revolving drum 24 is attached tothe robot base 22 so as to revolve about a vertical axis.

The robot arm 26 includes an upper arm 28 rotatably attached to therevolving drum 24, and a forearm 30 rotatably attached to a distal endof the upper arm 28. A wrist 32 is attached to a distal end of theforearm 30. In this embodiment, the robot 14 functions as a manipulatorwhich moves the imaging part 16 and the nozzle 18.

The imaging part 16 is attached to the wrist 32. The imaging part 16includes an imaging element comprised of e.g. a CCD or CMOS sensor, andan optical system comprised of e.g. a lens. The imaging part 16photoelectrically converts a subject image entering through the opticalsystem to image data, and outputs the image data.

The imaging part 16 images a region (i.e., the jig 104) on which theworkpiece is placed and transmits the image data to the controller 12,in accordance with a commands from the controller 12. The controller 12receives the image data from the imaging part 16, and stores it in astorage 34 (FIG. 2) built in the controller 12.

The nozzle 18 is attached to the wrist 32 via an attachment 36. As shownin FIG. 3, the nozzle 18 is a hollow member extending in the z-axisdirection in the orthogonal coordinate system in FIG. 3.

The nozzle 18 has a through-hole 38 extending through the center part ofthe nozzle 18 in the z-axis direction. The through-hole 38 extendsbetween a first opening 40 formed at an end part 18 a of the nozzle 18in the z-axis positive direction and a second opening 42 formed at anend part 18 b of the nozzle 18 in the z-axis negative direction.

The fluid supplying part 20 is fluidly connected to the nozzle 18 via afluid supplying pipe 44. The fluid supplying pipe 44 is connected to thefluid supplying part 20 at one end thereof, and is connected to thesecond opening 42 at the other end thereof.

The fluid supplying part 20 supplies fluid (e.g., compressed gas orcompressed liquid) into the through-hole 38 of the nozzle 18 via thefluid supplying pipe 44. The fluid supplied from the fluid supplyingpart 20 into the through-hole 38 of the nozzle 18 is injected from thefirst opening 40 to the outside.

In this embodiment, the orthogonal coordinate system in FIG. 3 is set asa tool coordinate system for defining a position and posture of thenozzle 18, and is pre-stored in the storage 34. The position and postureof the nozzle 18 in 3D space can be defined by 3D coordinates of originO, the x-axis direction, y-axis direction, and z-axis direction of thetool coordinate system. Note that, in this embodiment, the origin O isarranged at the center of the first opening 40.

The washing system 10 further includes a speaker 52 and a display 54.The speaker 52 outputs a sound wave in accordance with an audio signalreceived from the controller 12. The display 54 displays an image inaccordance with image data received from the controller 12.

Next, the operation principle of the washing system 10 will be describedwith reference to FIGS. 1 to 4. The washing system 10 removes chipsattaching on the jig 104 after the workpiece placed on the jig 104 isprocessed by the processing machine 102 and removed from the jig 104.

As shown in FIG. 4, the jig 104 according to this embodiment has arelatively complicated structure. In such a jig 104, there can be a zonein which removal of chips is difficult or a zone in which attachment ofchips significantly influences the processing accuracy, whereas therecan be a zone in which attachment of chips hardly influence theprocessing accuracy, (i.e., a zone for which washing is not necessary).

In this embodiment, a user predetermines a zone, in which chips shouldbe intensively removed, as a priority zone. For example, in the exampleshown in FIG. 4, a first zone 108 a, a second zone 108 b, a third zone108 c, and a fourth zone 108 d are set as priority zones within a region108 on the jig 104.

Such a priority zone can be predetermined by a user for each of variouskinds of workpieces. The storage 34 pre-stores the kind of the workpieceand the priority zone set for the workpiece in association with eachother.

For example, in the example shown in FIG. 4, the storage 34 pre-storesinformation of the first zone 108 a, the second zone 108 b, the thirdzone 108 c, and the fourth zone 108 d in association with the kind ofthe jig 104.

Thus, the controller 12 can recognize the first zone 108 a, the secondzone 108 b, the third zone 108 c, and the fourth zone 108 d, which areset for the jig 104.

The washing system 10 images the region 108 on the jig 104 before andafter the workpiece is processed, and detects chips present in the firstzone 108 a, the second zone 108 b, the third zone 108 c, and the fourthzone 108 d, on the basis of the image.

When the washing system 10 detects chips in any of the first zone 108 a,the second zone 108 b, the third zone 108 c, and the fourth zone 108 d,the washing system 10 injects the fluid to the chips so as to removethem.

Below, the operation flow of the washing system 10 will be describedwith reference to FIGS. 5 to 11. The flow shown in FIG. 5 is startedwhen the machine tool controller 106 receives a command for processing aworkpiece from a user, host controller or a processing program. When theflow shown in FIG. 5 is started, the controller 12 receives informationof the kind of a workpiece to be processed from the machine toolcontroller 106, the host controller or the processing program.

At step S1, the controller 12 images a region on which a workpiece isplaced. As an example, the controller 12 moves the robot 14 so as toarrange the imaging part 16 at a predetermined position above the jig104. The predetermined position is a position at which the imaging part16 can image the whole of the region 108 on the jig 104, and ispredetermined by a user.

As another example, the controller 12 may move the robot 14 so as tosuccessively arrange the imaging part 16 at a plurality of positionspredetermined by a user, and operate the imaging part 16 so as to imagethe region 108 on the jig 104 at each of the plurality of positions.

For example, in the jig 104 shown in FIG. 4, the controller 12 maysuccessively arrange the imaging part 16 at a first position at whichthe imaging part 16 can image an enlarged image (detailed image) of thefirst zone 108 a, a second position at which the imaging part 16 canimage an enlarged image of the second zone 108 b, a third position atwhich the imaging part 16 can image an enlarged image of the third zone,and a fourth position at which the imaging part 16 can image an enlargedimage of the fourth zone 108 d.

In this case, the storage 34 pre-stores information of the 3Dcoordinates of the first position, the second position, the thirdposition, and the fourth position, and of the posture (visual line data)of the imaging part 16 at each of these positions, in association withthe pre-stored information of the first zone 108 a, the second zone 108b, the third zone 108 c, and the fourth zone 108 d.

At step S1, the controller 12 reads out from the storage 34 the 3Dcoordinates of the first position, the second position, the thirdposition, and the fourth position, and data of the posture (visual linedata) of the imaging part 16 at each of these positions. Then, thecontroller 12 successively arranges the imaging part 16 at the firstposition, the second position, the third position, and the fourthposition, with changing the posture of the imaging part 16 to the oneset for each position.

The imaging part 16 respectively images enlarged images of the firstzone 108 a, the second zone 108 b, the third zone 108 c, and the fourthzone 108 d, at the first position, the second position, the thirdposition, and the fourth position, in accordance with a command from thecontroller 12. The imaging part 16 transmits the obtained image data tothe controller 12.

The controller 12 stores the image data received from the imaging part16 in the storage 34. By this step S1, the controller 12 operates theimaging part 16 so as to image the region 108 on the jig 104 before theworkpiece is placed on the region 108.

At step S2, the machine tool controller 106 carries out an operation forprocessing the workpiece. Specifically, the machine tool controller 106transmits a command to a workpiece carrying robot (e.g., the robot 14)so as to place the workpiece on the jig 104.

Then, the machine tool controller 106 transmits a command to theprocessing machine 102 so as to process the workpiece by the processingmachine 102. After the completion of processing the workpiece, themachine tool controller 106 transmits a command to the workpiececarrying robot so as to remove the workpiece from the inside of themachine tool 100.

At step S3, the controller 12 images the region on which the workpieceis placed, similar to above-mentioned step S1. Specifically, thecontroller 12 transmits a command to the robot 14 so as to arrange theimaging part 16 at the positions and postures the same as those at whichthe imaging part 16 has imaged the workpiece W at step S1, and operatesthe imaging part 16 so as to image the region 108 on the jig 104. Theimaging part 16 transmits the obtained image data to the controller 12.

The controller 12 stores the image data received from the imaging part16 in the storage 34. By this step S3, the controller 12 operates theimaging part 16 so as to image the region 108 after the workpiece isprocessed and removed from the region 108.

At step S4, the controller 12 executes an operation scheme 1. Step S4will be described below with reference to FIG. 6.

After step S4 is started, at step S11, the controller 12 detects whethera chip is present in the n-th zone (n=1, 2, 3, or 4). Note that, as willbe described later, the controller 12 repeats a loop of steps S11 to S16until it determines “YES” at step S16, after the start of step S4.

Below, a case is described where the controller 12 executes the firstloop of steps S11 to S16. When the controller 12 executes step S11 inthe first loop, the controller 12 sets the zone number “n” to “1” (i.e.,n=1), and detects whether a chip is present in the first zone 108 a atthis step S11.

Specifically, the controller 12 reads out from the storage 34 the imageswhich have been imaged by the imaging part 16 at each of steps S1 andS3.

An example of the image imaged at step S3 is shown in FIG. 8. In thiscase, chips A₀, A₁, A₃, and A₄ have been generated by the process on theworkpiece at step S2. More specifically, a chip A₁ is present in thefirst zone 108 a of the region 108.

Further, a chip A₃ is present in the third zone 108 c of the region 108.Further, a chip A₄ is present in the fourth zone 108 d of the region108. On the other hand, no chip is present in the second zone 108 b, andthere are a plurality of chips A₀ in the zone other than the first zone108 a, the second zone 108 b, the third zone 108 c, and the fourth zone108 d.

The controller 12 compares the image imaged at step S1 (e.g., the imageshown in FIG. 4) with the image imaged at step S3 (e.g., the image shownin FIG. 8) so as to calculate the difference in e.g. brightness or colorwavelength, and thereby the controller 12 detects the chip A₁ present inthe first zone 108 a.

Thus, in this embodiment, the controller 12 functions as a chipdetecting part 46 (FIG. 2) which detects a chip present in the region108 on the jig 104.

When the controller 12 detects the chip A₁ at step S11, it determines“YES”, and proceeds to step S12. On the other hand, when the controller12 does not detect the chip A₁ at step S11, it determines “NO”, andproceeds to step S15.

At step S12, the controller 12 determines a position and posture of thenozzle 18. In this embodiment, a user predetermines the position andposture (i.e., the tool coordinate system) of the nozzle 18 foreffectively removing a chip present in each of the first zone 108 a, thesecond zone 108 b, the third zone 108 c, and the fourth zone 108 d.

As an example, the tool coordinate system of the nozzle 18 is set sothat chips in the region 108 can be blown away radially outward from thecenter of the jig 104.

For example, as shown in FIG. 9, the tool coordinate system of thenozzle 18 is set as the orthogonal coordinate system in FIG. 9, in orderto blow away the chip A₁ in the first zone 108 a by the fluid injectedfrom the nozzle 18.

If the nozzle 18 is arranged at the tool coordinate system shown in FIG.9, the fluid injected from the nozzle 18 can blow away the chip A₁ in adirection D₁ (i.e., the z-axis positive direction in FIG. 9) towardradially outward from the center O of the jig 104.

The storage 34 pre-stores the tool coordinate system shown in FIG. 9,which is set for the first zone 108 a. At this step S12, the controller12 reads out from the storage 34 the tool coordinate system set for thefirst zone 108 a, and determines it as the position and posture at whichthe nozzle 18 is to be arranged.

Thus, in this embodiment, the controller 12 functions as an arrangementdetermining part 48 (FIG. 2) which determines the position and postureof the nozzle 18 when injecting the fluid to the chip A₁.

At step S13, the controller 12 operates the robot 14 so as to arrangethe nozzle 18 at the position and posture determined at step S12.Specifically, the controller 12 operates the robot 14 so as to arrangethe nozzle 18 at the tool coordinate system shown in FIG. 9.

Thus, in this embodiment, the controller 12 functions as a manipulatorcontroller 50 which controls the robot 14 (manipulator) so as to arrangethe nozzle 18 at the position and posture determined at step S12.

At step S14, the controller 12 injects the fluid from the nozzle 18.Specifically, the controller 12 transmits a command to the fluidsupplying part 20 so as to supply the fluid into the through-hole 38 viathe second opening 42 of the nozzle 18.

Due to this, the fluid is injected from the first opening 40 of thenozzle 18. The fluid injected from the first opening 40 impinges on thechip A₁ in the first zone 108 a. As a result, the chip A₁ is blown awayin the direction D₁.

At step S15, the controller 12 increments the zone number “n” by “1”.Specifically, when step S15 in the first loop is executed, the zonenumber “n” is incremented from “1” to “2” at step S15.

At step S16, the controller 12 determines whether the zone number “n”incremented at step S15 is greater than “4” (i.e., n>4). When thecontroller 12 determines that the zone number “n” is greater than “4”(i.e., determines “YES”), it proceeds to step S17.

On the other hand, when the controller 12 determines that the zonenumber “n” is not greater than “4” (i.e., determines “NO”), it returnsto step S11. In this way, the controller 12 repeats a loop of steps S11to S16 until it determines “YES” at step S16.

Next, a case is described below where the controller 12 executes thesecond loop of steps S11 to S16. At step S11 in the second loop, thecontroller 12 detects whether a chip is present in the second zone 108 b(i.e., the zone number n=2).

Specifically, the controller 12 compares the image imaged at step S1(FIG. 4) with the image imaged at step S3 (FIG. 8) so as to detect thechip in the second zone 108 b.

In the example shown in FIG. 8, there is no chip within the second zone108 b. Accordingly, the controller 12 determines “NO” at step S11, andproceeds to step S15. Then, the controller 12 increments the zone number“n” by “1” at step S15. Consequently, the zone number “n” is incrementedfrom “2” to “3”.

Then, the controller 12 determines “NO” at step S16 because the zonenumber “n” (=3) is not greater than 4, and returns to step S11.

Next, a case is described below where the controller 12 executes thethird loop of steps S11 to S16. At step S11 in the third loop, thecontroller 12 detects whether a chip is present in the third zone 108 c(i.e., the zone number n=3).

Specifically, the controller 12 compares the image imaged at step S1(FIG. 4) with the image imaged at step S3 (FIG. 8) so as to detect thechip A₃ in the third zone 108 c.

In the example shown in FIG. 8, the chip A₃ is present within the thirdzone 108 c. Accordingly, the controller 12 detects the chip A₃ anddetermines “YES” at step S11. Then, the controller 12 proceeds to stepS12.

At step S12, the controller 12 determines the position and posture ofthe nozzle 18. For example, as shown in FIG. 10, the tool coordinatesystem of the nozzle 18 in order to blow away the chip A₃ in the thirdzone 108 c is set as the orthogonal coordinate system in FIG. 10.

When the nozzle 18 is arranged at the tool coordinate system shown inFIG. 10, the chip A₃ can be blown away in a direction D₃ (i.e., thez-axis positive direction in FIG. 10) toward radially outward from thecenter O of the jig 104 by the fluid injected from the nozzle 18.

At this step S12, the controller 12 reads out from the storage 34 thetool coordinate system set for the third zone 108 c, and determines itas the position and posture at which the nozzle 18 is to be arranged.

At step S13, the controller 12 operates the robot 14 so as to arrangethe nozzle 18 at the position and posture determined at step S12. Then,at step S14, the controller 12 transmits a command to the fluidsupplying part 20 so as to inject the fluid from the first opening 40 ofthe nozzle 18. The fluid injected from the first opening 40 impinges onthe chip A₃ in the third zone 108 c, as a result of which, the chip A₃is blown away in the direction D₃.

At step S15, the controller 12 increments the zone number “n” by “1”.Consequently, the zone number “n” is incremented from “3” to “4”. Then,the controller 12 determines “NO” at step S16 because the zone number“n” (=4) is not greater than 4, and returns to step S11.

Next, a case is described below where the controller 12 executes thefourth loop of steps S11 to S16. At step S11 in the fourth loop, thecontroller 12 detects whether a chip is present in the fourth zone 108 d(i.e., the zone number n=4).

Specifically, the controller 12 compares the image imaged at step S1(FIG. 4) with the image imaged at step S3 (FIG. 8) so as to detect thechip A₄ in the fourth zone 108 d.

In the example shown in FIG. 8, the chip A₄ is present within the fourthzone 108 d. Accordingly, the controller 12 detects the chip A₄ anddetermines “YES” at step S11. Then, the controller 12 proceeds to stepS12.

At step S12, the controller 12 determines the position and posture ofthe nozzle 18. For example, as shown in FIG. 11, the tool coordinatesystem of the nozzle 18 in order to blow away the chip A₄ in the fourthzone 108 d is set as the orthogonal coordinate system in FIG. 11.

When the nozzle 18 is arranged at the tool coordinate system shown inFIG. 11, the chip A₄ can be blown away in a direction D₄ (i.e., thez-axis positive direction in FIG. 11) toward radially outward from thecenter O of the jig 104 by the fluid injected from the nozzle 18.

At this step S12, the controller 12 reads out from the storage 34 thetool coordinate system set for the fourth zone 108 d, and determines itas the position and posture at which the nozzle 18 is to be arranged.

At step S13, the controller 12 operates the robot 14 so as to arrangethe nozzle 18 at the position and posture determined at step S12. Then,at step S14, the controller 12 transmits a command to the fluidsupplying part 20 so as to inject the fluid from the first opening 40 ofthe nozzle 18. The fluid injected from the first opening 40 impinges onthe chip A₄ within the fourth zone 108 d, as a result of which, the chipA₄ is blown away in the direction D₄.

At step S15, the controller 12 increments the zone number “n” by “1”.Consequently, the zone number “n” is incremented from “4” to “5”. Atstep S16, the controller 12 determines “YES” because the zone number “n”(=5) is greater than 4 (i.e., n>4), and proceeds to step S17.

At step S17, the controller 12 determines whether no chip is detected inall zones 108 a, 108 b, 108 c, and 108 d. When the controller 12 detectsno chip in all of the first zone 108 a, the second zone 108 b, the thirdzone 108 c, and the fourth zone 108 d, it determines “YES” and ends theflow shown in FIG. 5.

On the other hand, when the controller 12 detects a chip in any of thefirst zone 108 a, the second zone 108 b, the third zone 108 c, and thefourth zone 108 d, it determines “NO” and proceeds to step S5.

In the example shown in FIG. 8, the chips A₁, A₃, and A₄ are detected inthe first zone 108 a, the third zone 108 c, and the fourth zone 108 d,and therefore the controller 12 determines “NO” at step S17, andproceeds to step S5.

Referring again to FIG. 5, at step S5, the controller 12 determineswhether the number of injections of fluid from the nozzle 18 exceeds apredetermined threshold value. As an example, the controller 12cumulates the number of injections of fluid every time the fluid isinjected from the nozzle 18, and determines whether the number ofinjections of fluid exceeds a predetermined number of times (e.g., 100times).

As another example, the controller 12 cumulates the number of injectionsof fluid from the nozzle 18 to the n-th zone (n=1, 2, 3, or 4), anddetermines whether the number of injections of fluid exceeds apredetermined number of times (e.g., 10 times).

The controller 12 proceeds to step S6 when it determines that the numberof injections of fluid from the nozzle 18 exceeds a threshold value(i.e., determines “YES”). On the other hand, the controller 12 returnsto step S3 when it determines that the number of injections of fluidfrom the nozzle 18 does not exceed a threshold value (i.e., determines“NO”).

When having determined “NO” at step S5, the controller 12 executes stepsS3 and S4 again. Consequently, the controller 12 detects a chipremaining in the zones 108 a, 108 b, 108 c, and 108 d just after step S4(step S11), and removes the detected chips (steps S12 to S14).

On the other hand, when having determined “YES” at step S5, thecontroller 12 executes an operation scheme 2 at step S6. Step S6 will bedescribed with reference to FIG. 7. Note that, processes in FIG. 7similar to those in FIGS. 5 and 6 are assigned the same referencenumerals, and the detailed description thereof will be omitted.

After step S6 is started, the controller 12 executes the above-mentionedstep S3. Specifically, the controller 12 transmits a command to therobot 14 so as to arrange the imaging part 16 at the position andposture at which the imaging part 16 has imaged the workpiece W at stepS3, and images the region 108 on the jig 104 by the imaging part 16.

Then, the controller 12 executes the above-mentioned step S11.Specifically, the controller 12 detects whether a chip is present in then-th zone (n=1, 2, 3, or 4). As will be described later, after step S6is started, the controller 12 repeats a loop of steps S11, S15, and S16until it determines “YES” at step S16.

For example, if the controller 12 executes step S11 in the third loop,the controller 12 detects whether the chip A₃ is present in the thirdzone 108 c.

The controller 12 proceeds to step S7 in FIG. 5 when it determines thata chip is present in the n-th zone (i.e., determines “YES”). On theother hand, the controller 12 proceeds to step S15 in FIG. 7 when itdetermines that there is no chip in the n-th zone (i.e., determines“NO”).

When having determined “NO” at step S11, the controller 12 executes theabove-mentioned step S15, and increments the zone number “n” by “1”.

Then, the controller 12 executes the above-mentioned step S16.Specifically, the controller 12 determines whether the zone number “n”incremented at step S15 is greater than 4. The controller 12 ends theflow shown in FIG. 5 when it determines that the zone number “n” isgreater than 4 (i.e., determines “YES”).

On the other hand, the controller 12 returns to step S11 when itdetermines that the zone number “n” is not greater than 4 (i.e.,determines “NO”). In this way, the controller 12 repeats the loop ofsteps S11, S15, and S16 until it determines “YES” at step S16.

Referring again to FIG. 5, at step S7, the controller 12 notifies a userof a warning. Specifically, the controller 12 generates an audio warningsignal and an image warning signal indicating that a chip is detected inthe zone 108 a, 108 b, 108 c, or 108 d even after the nozzle 18 injectsthe fluid for the number of times greater than a threshold value.

Then, the controller 12 transmits the audio warning signal and the imagewarning signal to the speaker 52 and the display 54, respectively. Thespeaker 52 and the display 54 output sound waves and images inaccordance with the warning signals received from the controller 12,thereby notify the user of the warning. Thus, in this embodiment, thecontroller 12 functions as a warning generating part 56 (FIG. 2) whichgenerates the warning for the user.

As described above, in this embodiment, the controller 12 detects a chipwithin the region 108 based on the image captured by the imaging part16, and determines the position and posture (the tool coordinate system)of the nozzle 18 suitable for injecting the fluid to the detected chip.

According to this configuration, a chip present in the region 108 can bereliably and automatically removed. As a result, it is possible toprevent the processing accuracy of the machine tool 100 from reducingdue to the chip.

Further, in this embodiment, the controller 12 detects the chips A₁, A₃,and A₄ in each of the zones 108 a, 108 b, 108 c, and 108 d which arepredetermined by a user, based on the image captured by the imaging part16.

In addition, the controller 12 determines the position and posture (thetool coordinate system) of the nozzle 18 suitable for removing thepresent chips A₁, A₃, and Au, for each of the zones 108 a, 108 b, 108 c,and 108 d.

According to this configuration, it is possible to reliably remove thechips A₁, A₃, and A₄ present in the zones 108 a, 108 b, 108 c, and 108 dset by a user, even if the jig 104 has a complicated structure.

Further, according to this embodiment, a user can predetermine the zones108 a, 108 b, 108 c, and 108 d within the region 108 on the jig 104 aspriority zones for which washing is especially needed.

In addition, the washing system 10 can reliably remove the chips A₁, A₃,and A₄ within the zones 108 a, 108 b, 108 c, and 108 d, while washingfor a region other than the priority zones can be omitted. According tothis configuration, since the number of washing can be reduced, it ispossible to reduce the cycle time of processing by the machine tool 100.

Further, in this embodiment, after washing the zones 108 a, 108 b, 108c, and 108 d at step S4, steps S3 and S4 are repeatedly executed unlessit is determined “YES” at step S5.

According to this configuration, since steps S3 and S4 are repeatedlyexecuted until no chip is detected within the zones 108 a, 108 b, 108 c,and 108 d, it is possible to reliably remove a chip within the zones 108a, 108 b, 108 c, and 108 d.

Further, in this embodiment, since the imaging part 16 and the nozzle 18are attached to the robot 14, it is possible to arrange the imaging part16 and the nozzle 18 at the appropriate position and posture just byselecting an operation program of the robot 14 corresponding to eachtype of jig. Due to this, it is possible to efficiently carry outwashing.

Further, in this embodiment, the controller 12 determines whether thenumber of injections of fluid exceeds the threshold value at step S5.When the controller 12 determines “YES” at step S5 and a chip isdetected in any of the zones 108 a, 108 b, 108 c, and 108 d at step S6,the controller 12 warns a user at step S7.

According to this configuration, since the number of washing carried outby the washing system 10 can be limited to a predetermined number oftimes, it is possible to prevent the washing system 10 from endlesslyrepeat washing due to occurrence of some abnormal event.

Note that, the “some abnormal event” includes an event in which ascratch occurs on any of the zones 108 a, 108 b, 108 c, and 108 d andthe controller 12 erroneously detects the scratch as a chip at step S11.

Further, the “some abnormal event” includes an event in which a chip orforeign substance, which cannot be removed only by injecting the fluidthereto from the nozzle 18, is attached to any of the zones 108 a, 108b, 108 c, and 108 d.

Note that, in the above-mentioned embodiments, the washing system 10includes the storage 34, the speaker 52, the display 54, and the warninggenerating part 56. However, these elements are not indispensable forthe invention.

Below, a washing system 60 according to another embodiment of theinvention will be described with reference to FIGS. 12 and 13. Notethat, in this embodiment, elements similar to those in theabove-mentioned embodiments are assigned the same reference numerals,and the detailed description thereof will be omitted.

The washing system 60 includes a controller 62, a robot 14, an imagingpart 16, a nozzle 18, and a fluid supplying part 20. The controller 62directly or indirectly controls each component of the washing system 60.Similar to the above-mentioned embodiments, the imaging part 16 and thenozzle 18 are attached to the robot 14, and moved by the robot 14 inaccordance with a command from the controller 62.

Next, the operation of the washing system 60 will be described. Thewashing system 60 detects chips A₁₀ in a region 112 on a jig 110 shownin FIG. 13, for example. The region 112 on the jig 110 is a region onwhich a workpiece to be processed is placed.

The controller 62 operates the robot 14 so as to arrange the imagingpart 16 at a predetermined position and posture, and transmits a commandto the imaging part 16 so as to image the region 112 (This correspondsto the above-mentioned step S1).

Then, the controller 62 functions as a chip detecting part 64 so as todetect the chips A₁₀ in the region 112 based on the image imaged by theimaging part 16 (This corresponds the above-mentioned step S11).

Then, the controller 62 functions as an arrangement determining part 66so as to determine the position and posture of the nozzle 18 suitablefor injecting the fluid to the detected chips A₁₀ (This corresponds tothe above-mentioned step S12).

For example, the controller 62 sets the tool coordinate system of thenozzle 18 as shown in FIG. 13. The tool coordinate system of the nozzle18 may be predetermined by a user. Alternatively, the controller 62 mayappropriately determine the position and posture of the nozzle 18suitable for blowing away the chips A₁₀, based on the position of thechips A₁₀ in the captured image.

Then, the controller 62 functions as a manipulator controller 68 so asto control the robot 14 to arrange the nozzle 18 at the determinedposition and posture (This corresponds to the above-mentioned step S13).Consequently, the nozzle 18 is arranged as shown in FIG. 13.

Then, the controller 62 transmits a command to the fluid supplying part20 so as to inject the fluid from the nozzle 18 to the chips A₁₀ (Thiscorresponds to the above-mentioned step S14). Consequently, the chipsA₁₀ in the region 112 can be blown away in a predetermined direction.

Note that, in the above-mentioned embodiments, the controllers 12 and 62are provided as components for controlling the robot 14 (i.e., as robotcontrollers) so as to be separate from the machine tool controller 106.

However, the controller 12, 62 may be provided as a component separatefrom the robot controller for controlling the robot 14. In this case,the controller 12, 62 may be incorporated in the machine tool controller106.

Further, in the embodiment shown in FIG. 2, the chip detecting part 46,the arrangement determining part 48, the manipulator controlling part50, the warning generating part 56, and the storage 34 are incorporatedin the controller 12.

However, at least one of the chip detecting part 46, the arrangementdetermining part 48, the manipulator controlling part 50, the warninggenerating part 56, and the storage 34 may be provided as a componentseparate from the controller 12.

Similarly, in the embodiment shown in FIG. 12, at least one of the chipdetecting part 64, the arrangement determining part 66, and themanipulator controlling part 68 may be provided as a component separatefrom the controller 12.

Further, in the above-mentioned embodiments, the robot 14 of a verticalarticulated type is employed as a manipulator which moves the imagingpart 16 and the nozzle 18. However, any manipulator able to move theimaging part 16 and the nozzle 18 may be employed.

Further, the controller 12 may transmit a command to the robot 14 so asto move the nozzle 18 when injecting the fluid from the nozzle 18 atstep S14 in FIG. 6. For example, the controller 12 transmits a commandto the robot 14 so as to swing the nozzle 18 in order to facilitate toremove a chip by the injected fluid during the execution of step S14.

Further, in the above-mentioned embodiments, the imaging part 16 isattached to the robot 14. However, the imaging part 16 may be fixed to apredetermined fixed point. The fixed point is set at a position at whichthe imaging part 16 can image the entirety of the jig 104.

Further, at step S11 in FIGS. 6 and 7, the controller 12 may detectwhether there are chips, the number of which is greater than apredetermined number, in the n-th zone. Specifically, the storage 34pre-stores the “predetermined number” of chips.

The controller 12 determines “YES” at step S11 when the number of chipsdetected in the n-th zone is greater than the predetermined number,while the controller 12 determines “NO” when the number of chipsdetected in the n-th zone is not greater than the predetermined number.

Although the invention has been described above through variousembodiments, the embodiments do not limit the inventions according tothe claims. Further, a configuration obtained by combining the featuresdescribed in the embodiments of the invention can be included in thetechnical scope of the invention. However, all combinations of thesefeatures are not necessarily essential for means for solving theinvention. Furthermore, it is obvious for a person skilled in the artthat various modifications or improvements can be applied to theembodiments.

Regarding the order of operations, such as actions, sequences, steps,processes, and stages, in the devices, systems, programs, and methodsindicated in the claims, specification and drawings, it should be notedthat the terms “before”, “prior to”, etc. are not explicitly described,and any order can be realized unless the output of a previous operationis used in the subsequent operation. Regarding the processing in theclaims, specification, and drawings, even when the order of operationsis described using the terms “first”, “next”, “subsequently”, “then”,etc., for convenience, maintaining this order is not necessarilyessential for working the inventions.

The invention claimed is:
 1. A washing system of a machine tool,comprising: a nozzle configured to inject fluid; a manipulatorconfigured to move the nozzle; a storage configured to store a pluralityof sets of position and posture of the nozzle when the fluid is injectedto a chip present in a plurality of priority zones defined within aregion on which a workpiece to be processed is placed, the sets ofposition and posture of the nozzle being predetermined with respect tothe respective priority zones; an imaging part configured to image theregion; a chip detecting part configured to detect whether or not a chipis present in each priority zone before a first fluid-injectionoperation by the nozzle onto each priority zone, based on an imageimaged by the imaging part; an arrangement determining part configuredto read out from the storage the set of position and posturecorresponding to the priority zone in which the presence of the chip isdetected by the chip detecting part, and determine the read-out set ofposition and posture as a position and posture of the nozzle when thefluid is injected to the chip present in the priority zone; amanipulator controller configured to control the manipulator so as toarrange the nozzle at the position and posture determined by thearrangement determining part; and a fluid supplying part configured tocarry out the first fluid-injection operation by supplying the fluid tothe nozzle so as to inject the fluid through the nozzle, when the nozzleis arranged at the position and posture determined by the arrangementdetermining part.
 2. The washing system according to claim 1, whereineach set of position and posture stored in the storage is determined sothat the fluid injected from the nozzle can blow away the chip in apredetermined direction.
 3. The washing system according to claim 1,wherein the imaging part is moved by the manipulator, wherein themanipulator controller operates the manipulator so as to arrange theimaging part at a plurality of positions at which the imaging part canimage enlarged images of the respective priority zones, wherein theimaging part images the region at each of the plurality of positions. 4.The washing system according to claim 1, wherein the imaging part imagesthe region again after the first fluid-injection operation, wherein thechip detecting part detects whether or not the chip remains in eachpriority zone before a second fluid-injection operation by the nozzleonto each priority zone, based on the image imaged by the imaging partafter the first fluid-injection operation, wherein the manipulatorcontroller operates the manipulator so as to arrange the nozzle again atthe position and posture, which has been determined by the arrangementdetermining part, when the fluid is injected to the chip present in thepriority zone in which the remain of the chip is detected by the chipdetecting part; wherein the fluid supplying part carries out the secondfluid-injection operation by supplying the fluid to the nozzle so as toinject the fluid through the nozzle again.
 5. The washing systemaccording to claim 4, further comprising a warning generating partconfigured to generate a warning when the number of injections of fluidfrom the nozzle exceeds a predetermined number.